1. Field of the Invention
The present invention relates to a log periodic antenna and a manufacturing method thereof, and more particularly to a log periodic antenna and a manufacturing method thereof that make antenna elements attached to an antenna body to thereby simplify a structure of the antenna, that enable the antenna to be manufactured in various designs without restriction to the configuration of the antenna, and that make the number of contacting points between the antenna element and a feeder to be minimized to thereby simplify the manufacturing process.
2. Description of the Prior Art
As generally known in the art, the log periodic antenna is a broadband antenna wherein the length ratio and the interval ratio of adjacent antenna elements are constant and wherein it has almost constant frequency response within the frequency range of the longitudinal-type antenna row.
The log periodic antenna is being widely used for receiving the digital broadcast ever since the latter was full-fledged. In the prior art, the antenna was mostly made of a rod-type element, but nowadays a different antenna with the antenna element printed on a PCB substrate is used.
The antenna made of the rod-type element has the disadvantages in that it is heavy and weak to the external impact because the rod is made from aluminum or stainless steel. However, the log periodic antenna on the PCB substrate has the advantages in that it is strong to the external impact, maintains stable receiving characteristics, and hides the antenna element to thereby improve the outer configuration of the antenna. Accordingly, the log periodic antenna is widely used as an outdoor antenna or an indoor antenna at home.
When manufacturing the above-described log periodic antenna, the steps of: partially etching a surface of a PCB substrate; printing a signal pattern at one side of the etched surface and a ground pattern at the other side of the etched surface; and connecting portions of the printed signal pattern and portions of the printed ground pattern to a feeder of the antenna by soldering without omission are included.
Korea Utility Model No. 0370996 discloses such a conventional log periodic antenna.
FIG. 1 is a bottom view of the conventional log periodic antenna. Referring to the drawing, antenna elements 21 are symmetrically printed at either side on a surface of a plane antenna 20. A feeder 24 extending across the middle of the plane antenna 20 is fixed.
As illustrated in FIG. 1, the antenna elements 21 are printed at either side of the plane antenna 20 wherein the signal pattern is printed at one side and the ground pattern is printed at the other side. The feeder 24 is disposed to extend across the antenna elements 21. Also, the contacting portions between the feeder 24 and the antenna elements 21 are connected by soldering.
In manufacturing the conventional antenna described above, the PCB substrate should be prepared beforehand to fit to the configuration of a main body of the antenna. Further, a pattern printing, which is deemed to be difficult in the field of the art, is needed to prepare the PCB substrate. Accordingly, it is impossible to change the configuration of the main body of the antenna after settling the patterns to be printed on the PCB substrate.
Moreover, the manufacturing process is rather complicated because the soldering should be performed to connect the antenna devices 21 to the feeder 24.